Bi3.4Eu0.6Ti3O12/Ni0.7< /sub>Cu0.3Fe2O4 films annealed under different atmosphere with enhanced magnetoelectric coupling effect

作者：Shi, Min^*; Men, Enyang; Xu, Yudong; Zuo, Ruzhong; Guo, Li; Si, Zhuolin; Hu, Kunzhuang; Chen, Hao; Bai, Tiancheng

来源：Ceramics International, 2022, 48(2): 2406-2414.

DOI：10.1016/j.ceramint.2021.10.021

• Magnetoelectric coupling effect
• Annealing atmosphere
• Spin-coating method
• Ferroelectricity
• Ferromagnetism

The single Bi4-xEuxTi3O12 and Ni1-xCuxFe2O4 films were prepared via spin-coating method. The composite films of the Bi3.4Eu0.6Ti3O12/Ni0.7Cu0.3Fe2O4, annealed under N-2, air and O-2, were also prepared via the same method. Compared with the films of Bi4Ti3O12, the films of the Eu-doped Bi4Ti3O12 (Bi4-xEuxTi3O12) exhibit enhanced ferroelectricity. And when x is equal to 0.6, the films of Bi4-xEuxTi3O12 show optimal ferroelectricity. Compared with the undoped NiFe2O4 film, in the films of Ni1-xCuxFe2O4, the doping of Cu2+ enhances ferromagnetism. And when x is equal to 0.3, the Ni1-xCuxFe2O4 films exhibit optimal ferromagnetism. For the composite films of Bi3.4Eu0.6Ti3O12/Ni0.7Cu0.3Fe2O4, annealing atmosphere has a significant impact on the magnetoelectric properties. In comparison with the composite films annealed under N-2 and air, the composite films annealed under O-2 exhibit optimum ferroelectricity (saturation polarization being 26.3 mu C.cm(-2)), ferromagnetism (saturation magnetization being 385.6 emu.cm(-3)) and enhanced magnetoelectric coupling effect (magnetoelectric voltage coefficient being 86.4 mV.(cm.Oe)(-1)). This is beneficial for the applications in magnetoelectric functional devices.